The present disclosure relates to solar roof tiles. More particularly, it relates to photovoltaic modules adapted for rapid installation as part of an arrayed, rooftop photovoltaic system.
Solar power has long been viewed as an important, highly viable, alternative energy source. To this end, substantial efforts and investments have been made to develop and improve upon solar energy collection technology. Of particular interest are industrial- or commercial-type applications in which relatively significant amounts of solar energy can be collected and utilized in supplementing or satisfying power needs.
Solar photovoltaic technology is generally viewed as the optimal approach for large scale solar energy collection, and can be used as a primary and/or secondary (or supplemental) energy source. In general terms, solar photovoltaic systems (or simply “photovoltaic systems”) employ solar panels made of silicon or other materials (e.g., III-V cells such as GaAs) to convert sunlight into electricity. More particularly, photovoltaic systems typically include a plurality of photovoltaic (PV) modules (or “solar tiles”) interconnected with wiring to one (or more) appropriate electrical components (e.g., switches, inverters, junction boxes, etc.). The PV module conventionally consists of a PV laminate or panel generally forming an assembly of crystalline or amorphous semiconductor devices electrically interconnected and encapsulated. One or more electrical conductors are carried by the PV laminate through which the solar-generated current is conducted.
Regardless of an exact construction of the PV laminate, most PV applications entail interconnecting an array of PV modules at the installation site in a location where sunlight is readily present. This is especially true for commercial or industrial applications in which a relatively large number of PV modules are desirable for generating substantial amounts of energy, with the rooftop of the commercial building providing a convenient surface at which the PV modules can be placed. As a point of reference, many commercial buildings have large, flat roofs that are inherently conducive to placement of a significant array of PV modules. In fact, utilizing an existing rooftop as the PV module installation site represents the most efficient use of space in that the building/rooftop structure is already in existence, and thus minimizes the need for additional, separate structures necessary for supporting the PV modules. While rooftop installation is thus highly viable, certain environment constraints must be addressed. For example, the PV laminate is generally flat or planar; thus, if simply “laid” on an otherwise flat rooftop, the PV laminate may not be positioned/oriented to collect a maximum amount of sunlight throughout the day. Instead, it is desirable to tilt the PV laminate at a slight angle relative to the rooftop (i.e., toward the southern sky for northern hemisphere installations, or toward the northern sky for southern hemisphere installations). Further, rooftop-installed PV modules are oftentimes subjected to windy conditions, a concern that is further heightened where the PV laminate is tilted relative to the rooftop as described above.
In light of the above, conventional PV module installation techniques have included physically interconnecting each individual PV module of module array directly with, or into, the existing rooftop structure. For example, some PV module configurations have included multiple frame members that are physically attached to the rooftop via bolts driven through the rooftop. While this technique may provide a more rigid mounting of the PV module to the rooftop, it is a time-consuming process, and inherently permanently damages the rooftop. Further, because holes are formed into the rooftop, the likelihood of water damage is highly prevalent. More recently, PV module configurations have been devised for commercial, flat rooftop installation sites in which the arrayed PV modules are self-maintained relative to the rooftop in a non-penetrating manner. More particularly, the PV modules are interconnected to one another via a series of separate, auxiliary components, with a combined weight of the interconnected array (and possibly additional ballast and/or wind-deflecting fairings or “wind deflectors” mounted to one or more of the PV modules at the installation site) serving to collectively offset wind-generated forces.
While the non-penetrating PV module array approach has been well-received, certain drawbacks may still exist. For example, a large number of parts are required, along with the logistical management of these parts, to facilitate non-penetrating, interconnected mounting of an array of PV modules. In this regard, the arrangement of PV modules (e.g., number, location, and type) will vary for each installation site. Thus, the number and types of requisite, auxiliary mounting components will also vary, and must be accurately ordered and delivered to the installation site with the PV modules. Thus, considerable upfront planning is necessary. Along these same lines, installation requirements for several non-penetrating PV module formats entail wind-deflecting auxiliary components (e.g., a perimeter curb) that are configured or sized as a direct function of the resultant perimeter shape or geometry of the arrayed PV modules. Once again, substantial upfront planning must be performed in order to ensure that these wind-deflecting components, as well as other installation components, are provided to the installation site in forms that are properly sized and shaped in accordance with the expected shape of the PV module array. Clearly, any errors in the upfront planning, miscommunication of the installation parameters, incorrect part list ordering, etc., can negatively impact and overtly delay the installation process. Further, where the auxiliary installation components are packaged apart from the PV modules, as is common in the industry, it is highly difficult at best for the installation personnel to quickly recognize whether ordering and/or shipping errors have occurred. Instead, these errors only become evident during the actual installation process, and typically cannot be quickly rectified. Similarly, fairly significant labor and expertise (and thus cost) is required to install non-penetrating PV modules at a commercial building's rooftop. Finally, considerable expense is necessitated by the handling and disposal of the shipping materials required in providing all of the PV modules, as well as all of the auxiliary mounting components and related equipment.
PV module-based solar energy represents an extremely promising technology for reducing the reliance of commercial or industrial businesses upon conventional, natural resource-based energy. To be competitive with traditional sources of municipal power, however, the costs associated with solar PV systems should desirably be reduced wherever possible. Thus, a need exists for a PV module and related PV module systems or arrays that are readily mounted to commercial rooftops in a non-penetrating fashion.